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uneven acceleration

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Not used The Boss for a while (its winter here in UK) But I did some full pedal to the carpet acceleration from rolling starts, Off corners/junctions/overtakes and the car seamed to accelerate unevenly. Back end squirmed a bit, not sure if this was due to worn out road surfaces or a slight dampness. End result was 444bhp didn't get put down smoothly. Cant say I noticed traction control lights coming on. Nothing was disabled.
As the Boss is rare here in UK I cant ask other owners easily, So I wondered if some cars do develop a fault with power delivery, Or I was being to ambitious and the Torsen diff was working overtime? And thats the feeling you get from the seat of your pants? An uneven feeling of being pushed forwards?
I have had a car in the past with a Quiafe ATB LSD, and it felt different to this.
Thanks in advance for any comments.
 
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cloud9 said:
There iis a noticable "hitch" around 4k RPMs with this engine occasionally. Is that where you noticed it or was it at all RPMs?

i have seen that before myself. i wrote it off as cold or an random misfire or something, glad im not the only one seeing it.
 
If the back end squirmed some it may just be the Traction Control kicking in. Before making any judgements. I would turn off all Nanies and then take it for your test drive. just be carefull if your not used to pushing it with everything turned off.
I assume that the car thru NO Codes. And is a stock tune.
Let us know. Your in the right place for a diagnose.
The Fourm service rates are the best 8).
The members hear are the Best and will help you as best as they can!
 
Yeah a 'hitch' might well describe it - nothing as serious as a misfire. and as the revs go through the 4k area could well cover it. I didn't want to hear of a sensor that needed replacing or oil related problem with the cams or some other nonsence! (like a Mazda MX5 throwing fault codes and just needing fresh oil !)

I'll try it with both the TC's turned off when I get the chance, Salty roads at present... :(
I think I was using The Track Key and it was cold out that last day I used it.

Thanks guys
 
There's two things I noticed with the stock Boss. The first is the wheel hop. It didn't sound like you were experience this, but the second thing is if you stomped on it, with damp roads, I'm betting that the wheels started spinning. Even if it was in dry condition, when the temperature is below about 55 degrees, the wheels (for me anyways) will break loose under heavy acceleration in 1st. The car goes and then the acceleration slows down. You should also hear the rpm of the motor correspondingly going up too quickly. At this point the LSD has locked up and you spinning both wheels. If I do spin the wheels in first, this is my queue to shift to second gear! If you were having ignition issues and it continues, you should start to get a Check Engine Light. Hope you figure it out.
 
Hi. It wasn't wheel hop for sure, It did it at speed but under full throttle, The revs didn't rise suddenly like they would (or do ... 8) from a standing start ! No strange noises, just this uneven feeling of thrust!

Next time out I'll take both keys & try it with TC's off!
 
I have noticed this on my Boss as well. I only sense the surges in the first few minutes of driving (under moderate acceleration). For reference I only drive with the track key. It always smooths out once the track key is active and the rest of the power train is up to operating temperatures.
 
Since I installed a vortech sc with a Jon Lund tune, I get uneven acceleration for the first few minutes also. I wrote it off as a cold engine. It seems to disappear when the engine warms up. I don't remember this hesitation prior to the vortech.


2012 BOSS302-Vortech SC
2003 Cobra-VMP TVS SC
 
What fuel are you running Simon, ive only used Shell 98 nitro and not noticed this effect although it could be like you say the Torsen as the roads are not really ready for your summer tyres yet, Im not sure if turning the traction control to ADV Trac will make the torsen less aggressive, someone on here can answer that i think though
 

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